以黑果枸杞为优势种的天然灌木群落是石羊河下游的重要植被建群种之一，为揭示该地区黑果枸杞种群动态变化特征，探索其生态价值，基于对石羊河下游不同生境黑果枸杞天然种群的样地调查，对其年龄结构、静态生命表、动态指数、存活曲线进行了分析研究。结果表明，不同立地类型黑果枸杞种群均表现为新苗和幼龄个体丰富，中老龄个体少；种群在Ⅲ龄级时死亡率最高，种群亏损率与死亡率保持一致。各样地种群动态指数基本为正值，说明黑果枸杞种群整体处于稳定增长的发育状态。盐碱地、覆沙地和砾石地黑果枸杞的存活曲线均接近于Deevey-Ⅲ型，固定/半固定沙地的存活曲线为Deevey-Ⅱ型。不同立地类型黑果枸杞种群的4个生存函数变化除局部有差异外整体趋势较为一致，各样地中黑果枸杞种群累积死亡率F(t)和危险系数λ(t)在Ⅰ龄级向Ⅲ龄级过渡时呈现逐渐增大的趋势，生存率S(t)和死亡密度函数f(t)随龄级呈单调递减的趋势。总体上黑果枸杞种群呈现出前期增长、中期稳定、后期衰退的特征。

Lycium barbarum is the dominant species in the natural shrub community in the lower reaches of Shiyang River and is considered as one of the constructive species as well. To reveal the population dynamic variation and to explore the ecological value of Lycium barbarum, the age structures, static life tables, dynamic indexes and survival functions of Lycium ruthenicum were analyzed. Results indicated that the population of different site types of Lycium ruthenicum showed abundance in both new seedlings and young individuals and less numbers for middle-aged and old individuals. The death rate of Lycium ruthenicum population was the highest at age Ⅲ, the loss rate was consistent with the death rate. The population dynamic indexes of various plots were basically positive values, which indicated that the population of Lycium ruthenicum was in a stable growth status. Survival curves of Lycium ruthenicum on the saline-alkali land, sandy land and gravel land were close to Deevey-Ⅲ type, the survival curves of Lycium ruthenicum on the fixed and semi-fixed sandy land were Deevey-II type. The changes of four survival functions of Lycium ruthenicum populationin different site types showed the same overall trend except for local differences. The death rate F(t) and danger coefficient λ(t) showed a trend of gradual increase and the survival rate S(t) and death density function f(t) of Lycium barbarum population showed a monotonous decreasing trend during the transition from Ⅰ to Ⅲ age class. Overall, the population of Lycium ruthenicum was increased in the early period, stable in the middle period and declining in the late period.

S567.19；S718.5

国家自然科学基金“石羊河下游非地带性土壤对黑果枸杞种群空间分布格局的影响机制”(31560128)、国家自然科学基金“干旱区地带性植物对土壤环境沼泽化的应急响应机制”(32060371)、甘肃省自然科学基金“石羊河下游青土湖典型植被固沙机制及其对风沙活动的响应”(20JR5RA095)。